By my calculation a 360 ppi print from a full D300 frame will be about 7.91″x11.91″. Letter is 8.5″x11″ and A4 is about 8.27″x11.69″, thus if you are printing the full frame with borders the native print resolution will be slightly greater than 360 and it may be worth testing 720 ppi for high frequency images. If you are printing borderless all bets are off, as the printer driver scales the image up larger than the nominal size in order to avoid any white borders - the amount is not specified hence you would not actually be printing at 360 or 720 ppi.

In addition your assumption of a changeover at around letter/A4 size is only true if you don't crop your image or if you don't stitch more than one image - in either of these cases you need to use the real dimensions of the image to be printed.

If you are printing borderless all bets are off, as the printer driver scales the image up larger than the nominal size in order to avoid any white borders - the amount is not specified hence you would not actually be printing at 360 or 720 ppi.

I've used borderless up to now. Heard comments in the video suggestion have some margin for the feeder mechanism. If I loose control over dimension used it seems like another reason stop using borderless?

For 4''x6'' the borderless format is still handy - can other confirm that the quality is reduced using this format or is this an issue only for large print?

My comment was not intended as a criticism of you, but I just wished the dimensions to be clear - I am European also, but have the advantage of being from England and had an education using mixed imperial and metric units and still tend to use a both for different things!

Quote

For 4''x6'' the borderless format is still handy - can other confirm that the quality is reduced using this format or is this an issue only for large print?

All standard inkjet printers from Canon, Epson or HP enlarge the image slightly when printing borderless. The manufacturers do not specify the percentage or if the percentage changes for different print sizes in any public documents I have seen. Because of this, trying to print at an exact printer resolution does not work as the enlargement factor means that the print is actually made at a slightly lower resolution. If the factor was known it might be possible to select a different resolution that would scale to the correct printer resolution (this might not be possible as only integer resolutions are usable). To determine the input resolution required it would be necessary to print a test pattern at various resolutions to determine the input resolution that resulted in the desired print resolution - this would have to be checked for any possible changes with paper size.

The purpose of printing at specific print resolutions is to produce the maximum quality print for extremely high quality work. Most users of the printers are not worried about the ultimate quality and do not bother to use the optimum resolution. All the current printers contain good print sizing algorithms that produce very good quality results even if the optimum resolution is not used. I would anticipate that your 4″x6″ prints are probably for a use that does not require the ultimate quality and that perfectly acceptable prints will be produced by either printing at native resolution or at 720 ppi. I would suggest that you compare the results of borderless at native resolution and 720 ppi with each other and with a 720 ppi print with borders and see which you prefer. (Note that if you are printing from Lightroom and the native resolution is greater than 720 ppi there will be no difference between the two borderless prints as LR only prints up to 720 ppi and down-samples all higher native resolutions to 720 ppi.)

No it isn't...if the native resolution is below 360, upsample to 360. If the native rez is above 360 but below 720, upsample to 720.

Actually, the discussion about whether or not to upsample is discussed elsewhere...this segment dealt with is it worth upsampling high native rez images to 720 (or 600).

(Edited to add second line since under review of the video, I didn't specifically mention under 360PPI images in this segment)

Hi Jeff, watching both LR3 tutorials and these newer ones I too understood to upsample by 50% while lower than a certain threshold.I was quite confused as I always thought to upres to the greater 360X multiplier just to avoid the job to be done by the printer/driver itself.

My question is: when upsizing from 360 to the final resolution (I'm speaking from the printer point of view when it receives the file from LR) will it use a serious algorithm or not?I mean, should I always send 720 ppi files to the printer so that LR manages to upres better that the printer itself?In worst case scenario, beside a longer time to export/send the file, it won't change nothing when printing from lower resolution, isn't it?

My question is: when upsizing from 360 to the final resolution (I'm speaking from the printer point of view when it receives the file from LR) will it use a serious algorithm or not?

What do you mean by "a serious algorithm"? In Lightroom, the upsampling will be done via an adaptive bicubic algorithm...bicubic for small changes and bicubic smoother for larger changes with an interpolation in between–which is something Photoshop can't do.

The rule I use now is to upsample to 360ppi for anything under 360 native. For anything above 360, I upsample to 720.

What I don't understand - in the Lieghtroom 3 videos Michael and Jeff explain that the option 'finest detail' is useable only when printig business charts. In the From Camera to print and screen vieos, Jeff explains that this option is th right one to use when upsampling an image to 720d(roplets)per inch.